Why do gallstones form?
Gallstones start as tiny crystals, then grow to resemble gravel, and may end up looking like pebbles. Sometimes, there is just a single stone; often there are several and it is not unknown for the gallbladder to contain literally dozens of small stones. Bile is a mixture of different chemicals. When the bile can no longer hold these chemicals in a liquid solution, gallstones start to form. Gallstones most frequently contain cholesterol. You may have heard of
cholesterol as a fatty substance in our diet that can cause disease in arteries. Cholesterol may be bad for arteries but the liver finds it very useful. Bile contains lots of cholesterol and indeed it is an important way for the body to clear itself of any excess. Bile may contain so much cholesterol that when it is stored in the gall bladder the cholesterol may separate out as little crystals, which may lump together to form a gallstone.
Who gets gallstones?
Gallstones are very common, but most people who have them do not know. By the age of 60 nearly a quarter of women (and a rather smaller number of men) will have developed some gallstones. The old saying that gallstones are seen in people with all the 'Fs' (fair, fat, female, fertile and forty) has some truth in it, since gallstones are commoner in women, especially those who have had children and who are overweight. However the age at which gallstones may give symptoms has changed a lot in recent years, and doctors see gallstones in much younger women, sometimes even teenagers, although it is certainly true to say they become commoner as we get older. They do seem to be getting rather more common generally, possibly as a result in changes in our diet over the last two generations.
Do they always cause symptoms?
Although gallstones may give rise to a number of different symptoms, they can be found quite incidentally in, for example, somebody who is having x-rays or ultrasound scans done for a completely different reason. Indeed doctors think that most people who get gallstones at some stage during their life are never aware that they have them. In that situation, such stones are best left alone unless they go on to cause symptoms. This only happens in a minority of patients.
What symptoms may gallstones cause?
It is not always clear why gallstones should cause problems for one individual yet leave another quite unaware of their presence. Gallstones usually only give rise to symptoms if they move from the gall bladder into one of the tubes (known as bile ducts) that lead from the gall bladder and the intestine. If they get stuck in the narrow neck of the gall bladder this can cause pain which can be quite severe. This type of pain is called biliary colic. Alternatively, the stones may cause inflammation in the wall of the gall bladder (known as cholecystitis).
If a stone gets into the main duct leading from the liver into the intestine it can give rise not only to pain from biliary colic but it may block the flow of bile from the liver altogether which causes jaundice. By far the commonest symptom caused by gallstones is biliary colic.
What is biliary colic?
Biliary colic is a pain that is felt in the top of the stomach, either in the middle or just under the ribs on the right hand side. It is usually a continuous pain but may come in waves. It is usually rather more severe than 'indigestion' and it is not uncommon for patients to feel so uncomfortable that they may seek medical advice. The pain usually lasts for a few hours and then goes away. Occasionally patients may feel sick or may vomit. The pain often follows a meal and may be noticed most often in the evenings – but one of the most irritating features of biliary colic is that it may occur at any time.
What is jaundice?
Jaundice (sometimes called yellow jaundice) is caused because the body is unable to get rid of bilirubin, which is a yellow chemical that occurs normally in the body. Bilirubin comes from red blood cells that have reached the end of their natural life, and it is one of the body's waste products that the liver has to deal with. The liver gets rid of bilirubin by mixing it in with bile. So, if a gallstone blocks the main duct leading from the liver into the intestine, bilirubin can't get out of the body and a yellow colour can be seen in the eyes and the skin. Some of the pigment does escape in the urine making it look a very dark colour.
What might make my doctor suspect that I have gallstones?
Your doctor might suspect gallstones if you have been getting pains anywhere round the top of your abdomen, particularly if these have been lasting for only a short time and coming occasionally. If you develop jaundice as well, your doctor would feel that it was very probable that you had gallstones. Your doctor would examine you to see if there was any soreness in the top of your abdomen, which is often the case, and might look at the whites of your eyes to see if there is any sign of jaundice.
What tests might I have?
Your doctor would probably arrange for you to have some blood tests to look for signs of inflammation or jaundice. The best test for gallstones is an ultrasound scan. This is a very easy scan to have, as a little probe is moved over the upper abdomen in the region of the liver and gall bladder, and usually it is very easy to pick out gallstones on the screen. Gallstones reflect ultrasound very well and are easily detected, unless they are deep in the abdomen or hidden behind some gas in the intestine. If the ultrasound scan does not give a clear result then other tests may be needed. Fortunately there are a number of different ways of scanning the gallbladder that enable doctors to say with confidence whether or not you have gallstones.
How are gallstones treated?
If they are not causing any symptoms, then it may not be necessary to have any treatment at all. Even if you have a single attack of pain from gallstones, there may be no further trouble for many years, if ever. This usually means that a single stone has travelled all the way out of the gall bladder, down the bile duct, into the intestine and has been passed naturally, so that in effect the patient has cured himself or herself of the problem. Gallstones are softer than kidney stones, so cannot be got rid of by fragmentation in the same way that kidney stones (which are hard and brittle) can. This means that in order to get rid of them gallstones have to be physically removed. This is usually done in one of two ways. If the gallstones are all contained in the gall bladder, then the simplest method is to have a small operation to remove the gall bladder and the stones within it. These operations can nowadays often be done with keyhole surgery, which means that patients recover from the operation within just a day or two, a huge improvement from the much larger operations that used to be necessary for gallstones in the past. The other way of dealing with gallstones, by endoscopy, is used for stones that have found their way into the common bile duct and caused a blockage there. Such stones can often be treated with ERCP (see below). Occasionally doctors might recommend other sorts of treatment.
Taking bile acids by mouth has largely gone out of vogue because treatment was lengthy, success rates were modest and recurrence of gallstones was frequent. In a very small number of patients, gallstones can be broken up by using shock waves. There is no question that, for most people, surgery is currently the best option for treating gallstones
What happens if I don't fancy having surgery?
If you have had episodes of pain that your doctor thinks are due to gallstones, it is likely that you will be offered surgery unless you are so unfit that an operation would be too risky. If you do not like the idea of surgery, you might choose to wait and see what happens to you. It is likely you will continue to have bouts of pain but most people with gallstones do not develop other complications. A small number of people will get jaundice but this can usually be readily treated as described above. Rarely, a gallstone can block the pancreas. This leads to a potentially serious complication called acute pancreatitis. If you are going to choose not to have surgery, do ensure that you are aware of the small risk that you are running.
What is ERCP?
ERCP (as it is usually known) means Endoscopic Retrograde Cholangio-Pancreatography, which is a complicated
way of describing a method in which gallstones may be removed with an endoscope so that surgery is unnecessary. A flexible endoscope is passed through the mouth, down to the stomach to reach the opening of the bile duct into the intestine.
A tiny tube is then passed through the endoscope and inserted into the lower end of the bile duct. If dye is squirted through this tube an X-ray picture of the duct can then be taken. The dye is squirted backwards (retrograde) up the duct and produces a picture of the bile duct (a cholangiogram) and also, if required, a picture of the pancreatic duct (pancreatogram), hence ERCP. If the cholangiogram confirms the presence of a stone in the duct this can either be removed or more often the bottom end of the duct can be enlarged so that the stone can pass out naturally. It is also possible to put little drainage tubes (stents) past the stones so that the bile can then, flow freely again.
These and similar techniques have the big advantage that an operation can be avoided, which is particularly useful in older or frailer patients.
Can people manage without a gall bladder?
Yes. If there is no gall bladder, bile just dribbles continuously into the intestine, rather than being reserved purely for after meals, as is the case if the gall bladder is functioning normally. There is no problem with digestion and people do not have any after-effects from their gall bladder having been removed.
What research is needed?
We need to know why gallstones have been becoming more common in recent years. It should then be possible to help to prevent them and their complications in the future. Although keyhole surgery has been a huge advance, like all surgical procedures, there can be complications. Gallstones are such a common problem that we need imaginative researchers to come up with non-surgical methods of treating them.